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demonising the dingo： How much wild dogma is enough？

Current Zoology 2011年第5期57卷 668-670页

作者： mike LETNIC Mathew S. CROWTHER Christopher R. dICKMAN Euan G. RITCHIE Hawkesbury Institute for the Environment University of Western Sydney Locked Bag 1797 Penrith NSW 2751 Australia Institute of Wildlife Research School of Biological Sciences University of Sydney NSW 2006 Australia School of Life and Environmental Sciences Deakin University Burwood Victoria 3125 Australia

The roles that top predators play in regulating the structure and function of ecosystems have long been controversial. This is particularly the case when predators pose adverse risks for human life and/or economic interests. The critique of literature on dingoes and their ecological roles in Australia provided by Allen et al. （2011） shows that top predators remain a potentially polarising issue. In opposition to Allen et al. we argue that these widespread patterns of species＇ abundances, attributed to the ef- fects of dingoes and evident at scales ranging from the foraging behaviour of individuals through to continental scale patterns of species abundances, constitute strong support for the mesopredator release hypothesis and provide evidence that dingoes benefit biodiversity conservation by inducing community wide trophic cascades. Harnessing the positive ecological effects of dingoes while at the same time minimising their impacts on agriculture is a major socio-political challenge in Australia [Current Zoology 57 （5）： 668-670].

关键词： Trophic cascade Mesopredator release hypothesis dingo fox Intra-guild predation

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Microbial diversity of Planctomycetes and Related Bacteria in Wetlands with different Anthropogenic disturbances

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湿地科学 2013年第2期11卷 158-166页

作者： Yu Wang Guibing Zhu Erwin van der Biezen mike S M Jetten Chengqing Yin State Key Laboratory of Environmental Aquatic Quality Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences department of Microbiology Institute for Water and Wetland Research (IWWR) Radboud University Nijmegen

The diversity of Planctomycetes and related bacteria in 3 types of freshwater wetlands with different anthropogenic disturbances were investigated by cloning and sequencing PCR-amplified partial 16S rRNA genes. Three clone libraries were constructed using 16S rRNA-targeted forward PCR primer specific for Planctomycetales and general bacterial reverse primer. Phylogenetic analysis of the 16S rRNA gene sequences defined 95 operational taxonomic units (OTUs) with 163 sequences. The clone libraries covered a wide microbial diversity of Proteobacteria and the Planctomycetes-Verrucomicrobia-Chlamydiales (PVC) superphylum. The majority of the OTUs were related to the phylum of Planctomycetes (33 OTUs), Proteobacteria (22 OTUs) and Verrucomicrobia (22 OTUs). Four known genera from the Planctomycetes phylum were all detected. The genus Pirellula (18 OTUs) dominated the Planctomycetes community, but different patterns of distribution were observed in the wetlands. The littoral wetlands of Baiyangdian Lake with the least anthropogenic disturbances covered more species and showed the highest biodiversity. However, the Jiaxing paddy fields with the highest anthropogenic disturbances showed a higher biodiversity than that in the riparian wetlands of the North Canal. Bacteria distantly related to anammox bacteria were also detected with a small proportion (4 OTUs). It showed that wetlands hold a great biodiversity of phyla Planctomycetes and related bacteria; furthermore, there is ample opportunity to discover novel phylotypes of Planctomycetes in the wetland ecosystems.

关键词： Planctomycetes biodiversity PVC superphylum anthropogenic disturbances freshwater wetlands

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Modern Shale Gas Horizontal drilling： Review of Best Practices for Exploration Phase Planning and Execution

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中国石油勘探 2009年第3期14卷 41-50页

作者： Nathaniel Harding Stephen Smith John Shelton mike d. Burnaman Harding Shelton Group Oklahoma City Oklahoma 73102

The challenging characteristics of shale formations often require horizontal drilling to economically develop their potential. While every shale gas play is unique, there are several best practices for the proper planning and execution of a horizontal well. In planning a horizontal well, the optimal method and technology for building inclination and extending the lateral section must be determined. Properly specified logging-while-drilling tools are essential to keep the wellbore within the target formation. Planning must also focus on casing design. doing so will help ensure stability and enable reliable and productive completions. Shales pose a challenge for these elements of well planning due to their thin strata and potentially low mechanical competence when foreign fluids are introduced. Once a plan is developed, executing it is even more important to prove a viable exploration program. Fast, efficient drilling with wellbore control and minimal torque and drag should be the priority. This may be achieved by focusing on fluid hydraulics and rheology and bottom hole assembly. Managed pressure drilling (MPd) will help fast drilling, well control and stability. If MPd can be combined with new generation rotary steerable systems that allow the drill string to maintain rotation, impressive efficiencies are possible. Modern drilling parameter analysis represents the newest opportunity for executing shale gas horizontal wells. A method for ROP analysis to improve operational parameters and equipment selection is also proposed.

关键词：页岩天然气石油地质勘探

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Spreadability of powders for additive manufacturing:A critical review of metrics and characterisation methods

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Particuology 2024年第10期93卷 211-234页

作者： Fatemeh A.Talebi Zobaideh Haydari Hamid Salehi Mozhdeh Mehrabi Jabbar Gardy mike Bradley Andrew E.Bayly Ali Hassanpour School of Chemical and Process Engineering University of LeedsLeedsLS29JTUK School of Engineering University of GreenwichGreenwichME44TBUK Cormica Limited Listerhills Science ParkCampus RoadBradfordBD71HRUK

Powder bed fusion methods of additive manufacturing (AM) require consistent, reproducible, and uniform layers of powder for the reliable production of high-quality parts, where properties of powder are central to achieving this. Among these properties, powder flowability and spreadability play critical roles in determining the quality of these powder *** extensive research has been conducted on powder flow and spreading behaviour, and on their characterisation, there is little critical comparison and review of these terms in the context of AM. Such a review is necessary to further develop and enhance our comprehension of spreading dynamics and its relation to powder properties in AM *** review paper aims to build a coherent understanding of the correlation between powder characteristics and spreading in powder based additive manufacturing and its impact on manufactured parts. It highlights the current progress in comprehending spreading dynamics, the influence of powder characteristics, environmental conditions, spreading system, and the development of testing tools to assess powder spreadability. Furthermore, the paper critically discusses the challenge of finding appropriate quantitative metrics and recent advances in the use of standardised methods for evaluating powder spreadability.

关键词： Powder spreading Powder flowability Powder properties Quality of layer and final products

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A COMPARISON OF EASTERN ANd WESTERN HONG KONG PHYTOPLANKTON FROM WEEKLY SAMPLES (1997-1999)

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Chinese Journal of Oceanology and Limnology 2002年第1期20卷 52-61页

作者： mike dickman 唐森铭 Jessie Lai 221 South 12th Ave. Bozeman Montana 59715 USA Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Ecology and Biodiversity dept. The University of Hong Kong Pokfulam Rd. Hong Kong

Weekly phytoplankton samples were taken from western Hong Kong (Lamma) from Jan. 1997 to dec. 1999 and from Port Shelter in Eastern Hong Kong from January 1998 to december 1999. during that time diatom blooms occurred repeatedly at both sites but never in synchrony. One species would bloom at one site and then weeks later it or another species would bloom at the other site; while the 1998 red tide of the mucus producing dinoflagellate Gymnodinium mikimotoi occurred at both sites. It first occurred at the Port Shelter site in March and did not appear at the Lamma site until April. With the single exception of this species, no other dinoflagellate reached bloom concentrations at the Lamma site. In addition, dinoflagellate abundance at the Lamma site was significantly lower (P d with a significantly higher turbidity (i.e. low Secchi transparency) and higher turbulence (stronger currents) at the Lamma site. Annual variation in surface temperature correlated with total surface phytoplankton abundance at both our sample sites. Phytoplankton abundance increased in spring as water temperatures warmed. In fall, as surface water temperatures began to decline and the monsoon rains became less frequent there was a reduction in phytoplankton abundance associated with the reduction in temperature and light. Because so many variables co-occur with temperature (e.g. the amount of rainfall, light intensity and light duration etc.) it is not possible to cite temperature as the causal factor associated weth controlling phytoplankton abundance at our two sample sites. Our data support the rather controversial notion that percentage-wise, there are relatively more harmful bloom forming species in nutrient-rich coastal waters than there are in the world’s oceans. 16% of the dinoflagellate species and 10.3% of the diatom species observed at our two sample sites were classed as harmful. These percentages were higher than those ci

关键词： red tides phytoplankton periodicity South China Sea harmful algal blooms

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